Low urinary estrogen glucuronides in women at risk for familial breast cancer.

Daily (12-hour) urine collections taken throughout the menstrual cycle were obtained from 30 young women who by genetic analysis were at risk for familial breast cancer, and from 30 control women carefully matched for age, height, and reproductive history. Steroids in the urine were extracted by glucuronidase hydrolysis, and the primary glucocorticoid, androgen, and estrogen hormones and their metabolites were measured by radioimmunoassay. Highly significant differences were observed only in the case of estrone and estradiol, with the high-risk subjects exhibiting lower values that the controls. This endocrine abnormality in young women at risk for breast cancer may be a potential discriminant for identifying women at risk for the disease in the population at large.